select
    substr(login_datetime, 1, 10) as FIRST_LOGIN,
    count(distinct member_code) as MEMBER_CNT
from access_log as a
inner join (
    select
        member_code,
        min(login_datetime) as login_datetime
    from access_log
    group by 1
    having min(login_datetime) like '2023-08-%'
) as b
using(member_code, login_datetime)
group by 1
order by 1 desc;